He spent much of Friday attempting to undo the damage done by an explosive interview with The Sun, in which he indicated he would not do a trade deal with Britain if he considered a soft Brexit to have been passed.

He had also told The Sun he offered Mrs May advice on how to handle the negotiations, and his former chief strategist Steve Bannon has revealed the president’s tips came from his book, The Art Of The Deal.

In that, he tells people to overshoot – asking for far more than they ever expect.

Mr Bannon told The Daily Telegraph that Mr Trump offered this advice to Mrs May, as well as advising her to be brutal and tough.

He added: Trump gave her some pointers and pulled her off to the side and said ‘Hey, if I was doing this, here is how tough you have got to be because these guys are not going to let you go’.

He gave her the precis [of his book], which is ‘overshoot your target and get on with it – because if this drags on it is going to be bad’.

Following talks with the prime minister at her Chequers country retreat, the US president backtracked on his claim Mrs May’s Brexit blueprint will kill hopes of any future US-UK trade dealand hailed US-UK ties as the highest level of special.

Mr Trump repeated his call for the UK to retain the ability to sign new trade agreements once it leaves the EU, but signalled he had received assurances from Mrs May this would be the case.

Addressing the row at a joint news conference with Mrs May on Friday, Mr Trump claimed he didn’t criticise Mrs May and has a lot of respect for her.

He said: The only thing I ask of Theresa is that we make sure we can trade and we don’t have any restrictions because we want to trade with the UK and the UK wants to trade with us.

So if they go in a slightly different route [on Brexit] – and I know they do want independence… if they are going to go in a certain route I just said that I hope you are going to be able to trade with the United States.

I read reports where that won’t be possible, but I believe after speaking with the prime minister’s people and representatives and trade experts it will absolutely be possible.

He said he had apologised to Mrs May for the report and praised her professionalism in her response.

He continued: She said ‘don’t worry it’s only the press’. I thought that was very professional.

She’s a very smart, very tough, very capable person and I would much rather have her as my friend than my enemy, that I can tell you.